JPS6138667A - Picture frame coating method of steel sheet - Google Patents

Abstract

PURPOSE:To improve working efficiency in picture frame coating of a steel sheet by eliminating application stage of masking tape by executing picture frame coating using two kinds of paint spray nozzle and masking sheet on a conveying line of the steel sheet. CONSTITUTION:When a front edge of steel sheet conveyed on a conveying line reaches a specified position, a first paint spray nozzle 2 begins operation. In this stage, a precoating zone 6a is formed by a distance S2 inside from the front edge of the steel sheet 1 and by a distance S1 inside from the side edge of the steel sheet 1. When the steel sheet 1 moves forward and the back edge reaches specified position, the nozzle 2 stops operation. Thus, the precoating zone 6a ends at a position by a distance S2 inside from the back edge of the steel sheet 1. Then, a range of the steel sheet 1 by the specified distance S2 inside from the front and back edges of the steel sheet 1 is covered with a masking plate 7. The whole area 6b of the front and rear surface of the steel sheet 1 surrounded by the precoated zone 6a and the masking plate 7 is coated with a second paint spray nozzle 8.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a picture frame painting method for painting all but a predetermined width of four edges on the front and back surfaces of a moving steel plate.

(b) Conventional technology When steel plates are coated with paint, etc., there are problems such as the paint decomposing during welding, emitting toxic gases, and causing welding defects such as blow holes, which can cause welding lines. A so-called picture-frame coated steel plate is manufactured in which unpainted portions are formed on all sides of the steel plate edge.

Frame-painted steel plates are painted on non-painted areas before painting using a coating device equipped with a conveyor platform that moves the steel plate and a coating nozzle that moves back and forth in the width direction of the steel plate and sprays paint onto the steel plate. It was manufactured by attaching tape to the edge of the steel plate in advance, applying paint on top of it, and peeling off the tape after painting.

However, this method requires a lot of time and effort to apply and peel off the tape, and is not efficient. Therefore, a coating device was developed that places shielding plates close to the top along both edges of the steel plate when the steel plate passes through the coating area, and automatically forms a non-coated area on the steel plate in both grades. It was done. This device has significantly reduced the amount of work required. However, even in this device, the process of attaching tape remains as a final step for edging the front and rear edges in the direction perpendicular to both edges of the back surface of the steel plate. Therefore, in recent years, when the demand for this type of steel plate has been increasing, the above-mentioned equipment is insufficient for mass production, and there has been a strong desire to develop a picture frame coating method suitable for mass production.

←Problem to be Solved by the Invention The problem to be solved by the present invention is to obtain a method for painting a picture frame with copper strips that does not require the step of pasting a shielding tape.

B) Means for Solving the Problems The method for painting a frame on a steel plate of the present invention is a method for painting a frame on a running steel plate except for a predetermined width on the four edges on the front and back sides. forming a coating band along the side edge and leaving an unpainted part of a predetermined width a predetermined distance inward from the side edge using a first paint spray nozzle provided near the side line in the longitudinal direction of the steel plate on the conveying line; controlling the operation of the first paint spray nozzle so that the start and end points of the pre-painting zone are a predetermined distance inward from the front and rear edges of the steel plate; The above problem is solved by coating the entire area surrounded by the pre-coating zone and the shielding plate with a second paint spray nozzle that moves back and forth in the width direction of the steel plate on the conveyance line of the steel plate. ing.

((e) Example) Next, an example of the method of the present invention will be described with reference to the drawings.

In FIGS. 2 and 3, a first paint spray nozzle 2 is provided on the conveyance line of the steel plate 1 near the side line in the longitudinal direction of the steel plate 1. As shown in FIG. More specifically, the nozzle 2 is installed so as to be inclined at a predetermined angle θ toward the front and back surfaces of the steel plate 1 with respect to both side edges thereof.

A baffle plate 3 is provided in front of the nozzle 2.

The nozzle 2 and the baffle plate 3 are supported by a commonly used support mechanism 4 so that the width direction, the vertical direction, the inclination angle θ, etc. of the steel plate 1 can be adjusted. A touch roller 5 is attached to the baffle plate 3 and rotatably contacts the side edge of the steel plate 1. The touch roller 5 functions to cause the baffle plate 3 to follow the positional change of the side edge of the steel plate 1.

As shown in FIG. 2, the nozzle 2 is installed at a predetermined angle θ with respect to the front or back surface of the steel plate 1, so that the paint 6 sprayed from the nozzle 2 is applied to the side edge of the steel plate 1. The paint is sprayed inward by a predetermined distance S to form a pre-painted band 6a having a predetermined width B.

The baffle plate 3 functions to restrict the course of the spray paint 6 so that the spray paint 6 does not go around inside the distance S1.

Next, the steps of the method of the present invention will be explained with reference to FIG.

The nozzle 2 does not start operating until the leading edge of the steel plate 1 reaches a predetermined position (A). This is to prevent painting from a predetermined distance S2 from the front edge of the steel plate 1, as will be described later.

When the leading edge of the steel plate 1 reaches a predetermined position, the operation of the nozzle 2 is started (B). At this time, the pre-painted strip 6a is the steel strip 1
is formed a distance S2 inward from the front edge of the steel plate 1 and a distance S inward from the side edge of the steel plate 1.

When the steel plate 1 advances and the trailing edge of the steel plate 1 reaches a predetermined position, the operation of the nozzle 2 is stopped (C).

As will be described later, this is a predetermined distance S from the trailing edge of the steel plate 1.
This is to prevent 2 from being painted. In this way, the pre-painting strip 6a extends inwardly from the trailing edge of the steel plate 1 by a distance S2 and ends there.

A shielding plate 7 is inserted a predetermined distance S2 inward from the front and rear edges of the steel plate 1.
Cover it with paint and send it to the next painting process (D).

In this coating process, the entire range 6b of the front and back surfaces of the steel plate 1 surrounded by the pre-coating zone 6a and the shielding plate 7 is coated by the second paint spray nozzle 8 (K). The nozzle 8 is configured to reciprocate in the width direction of the steel plate 10 on the conveyance line of the steel plate 1.

In this way, the steel plate 1 has a predetermined width S of the four edges on the front and back surfaces.
All except I and S2 are painted (F).

(f) Effects According to the method of the present invention, since shielding sheets are used only on the front and rear edges of the steel plate, the equipment is simplified compared to the conventional method, and automation of painting becomes easier. Since there is no need to apply shielding tape, clean the shielding portion of the copper plate, etc., it is possible to improve painting efficiency and reduce costs.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing the steps of the method of the present invention. FIG. 2 is an explanatory view showing the process of forming a pre-painting band on the longitudinal side edge of a steel plate. FIG. 3 is a plan view of an apparatus for carrying out the process shown in FIG. 2. 1: Steel plate 2: First paint spray nozzle: 3: Baffle plate 4: Support mechanism 5: Touch roller 6: Spray paint 6a: Pre-paint zone 7: Shield plate 8: Second paint spray nozzle Figure 1 (D) (E) (C) (F)

Claims (1)

[Claims] In a frame painting method in which all but a predetermined width of the four edges of the front and back surfaces of a traveling steel plate are painted, a first paint spray nozzle installed near the longitudinal side edge of the steel plate on the conveyance line of the steel plate is used. Therefore, forming a coating band in advance along the side edge and leaving an unpainted part of a predetermined width a predetermined distance inward from the side edge;
controlling the operation of the first paint spray nozzle so that the start and end points of the pre-painting zone are a predetermined distance inward from the front and rear edges of the steel plate; and coating the entire area surrounded by the pre-coating zone and the shielding plate using a second paint spray nozzle that moves back and forth in the width direction of the steel plate on the steel plate conveyance line. How to paint a steel plate picture frame.